<?php
function &get_config(){
    static $_config;
    if( !empty($_config) ){
        return $_config[0];
    }
    $config = array('user'=>'123');
    return $_config[0] = & $config;;
}

$t1 = &get_config();
print_r($t1);

$t1['test'] = 123;

$t1 = &get_config();
print_r($t1);
